Molding method of thermoplastic woven composite material propeller blade
Through the combination of thermoplastic filaments and high-performance fiber yarns and automated forming technology, the problem of low molding efficiency of thermoplastic braided composite propeller blades is solved, and efficient automatic forming and reducing material losses are achieved.
Patent Information
- Application Number
- CN202411447844.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-16
- Publication Date
- 2024-12-13
AI Technical Summary
Traditional RTM molding is difficult to achieve mold filling of thermoplastic resin, resulting in low molding efficiency of thermoplastic braided composite propeller blades and high material loss.
The thermoplastic filaments are combined with high-performance fiber yarns, and the resin melt is formed by heating and pressing and extruding to coat the fiber yarns to form a braided composite yarn, and the wire converging machine and robotic arms are used to achieve efficient and automated molding of propeller blades. The molding is completed in combination with the molding process.
It realizes efficient and automated forming of the thermoplastic braided composite propeller blades in complex special-shaped curved surfaces, reduces production costs, and significantly improves the friction resistance of the yarn, and reduces defects that affect mechanical properties such as fiber broken wire and kink.
Smart Images
Figure CN119116423A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to a method for molding a thermoplastic braided composite propeller blade, and belongs to the technical field of composite material molding. Background Art
[0002] Three-dimensional braided composite materials have excellent properties such as light weight, high strength, good structural designability and easy complex component molding. They are widely used in aerospace, transportation, military energy and other fields, such as rocket throat linings, propeller blades, engine nozzles, missile nose cones and carbon fiber frames. The corresponding two-dimensional braiding technology has the advantages of less material loss and high degree of automation, so it can realize the one-time molding of complex components, which is very suitable for the molding of various curved surfaces and special-shaped structural parts.
[0003] With the development of green economy, thermoplastic composites have become a hot research topic in scientific research and industry because of their recyclability. In the face of thermoplastic complex-shaped braided composites, it is difficult to achieve resin filling in traditional RTM molding due to the high viscosity of thermoplastic resin. Therefore, in order to solve the molding problem of thermoplastic braided composites, it is necessary to propose an innovative thermoplastic braided composite yarn forming method suitable for thermoplastic braided composite molding to overcome the defects of the existing technology. Summary of the invention
[0004] In view of this, the present application provides a molding method for thermoplastic braided composite propeller blades, which can achieve efficient and automated molding of thermoplastic braided composite propeller blades with complex special-shaped curved surfaces.
[0005] Specifically, the present application is implemented through the following scheme: A method for forming a thermoplastic braided composite propeller blade, the steps are as follows: Step 1: using thermoplastic filaments and high-performance fiber yarns as raw materials, the thermoplastic filaments are heated to form a resin melt, which is then pressurized and extruded to coat the high-performance fiber yarns, and then cooled to obtain a braided composite yarn; Step 2, winding the braided composite yarn on a spindle using a doubling machine to form a yarn shaft for the braiding machine; Step 3: The propeller blade core mold is fixed on the mechanical arm through a three-claw chuck and corresponds to the position of the yarn shaft of the braiding machine. The braiding machine and the mechanical arm are started to make the braided composite yarn braided and coated on the surface of the propeller blade core mold according to the set rules to obtain a braided composite preform; Step 4: placing the braided composite preform in a molding die, heating and molding it to obtain a thermoplastic braided composite propeller blade.
[0006] The above scheme uses thermoplastic filaments and high-performance fiber yarns as raw materials. The thermoplastic filaments are heated to form a resin melt, and the resin melt is then combined with the high-performance fiber yarn at a certain pressure through an air compressor, etc., so that it covers the high-performance fiber yarn to finally form a thermoplastic braided composite yarn. The characteristic of the yarn is that the thermoplastic filaments are completely filled between the high-performance fiber yarns after heating, so that the high-performance fibers cannot be displaced from each other. The flexibility of the thermoplastic braided composite yarn is lower than that of the high-performance fiber yarn, but the fiber surface is coated with thermoplastic resin, which can significantly improve the friction resistance of the yarn, reduce damage during the yarn weaving process, and reduce the fatal defects of the final composite material such as fiber breakage and kinking that affect the mechanical properties.
[0007] Further, as a preference: The thermoplastic filament is any one of polyamide (PA, nylon), polyetheretherketone (PEEK), polyethylene (PE) and polyurethane (PU).
[0008] The high-performance fiber yarn is any one of carbon fiber, quartz fiber, silicon carbide fiber and basalt fiber.
[0009] In step one: In the process of heating thermoplastic fibers to form resin melt, the heating temperature of polyamide (PA, nylon) is preferably controlled at around 240°C, the heating temperature of polyetheretherketone (PEEK) is preferably controlled at around 340°C, the heating temperature of polyethylene (PE) is preferably controlled at around 160°C, and the heating temperature of polyurethane (PU) is preferably controlled at around 200°C.
[0010] The pressurization refers to setting the pressure at 0.1-0.3 MPa.
[0011] The resin melt formed by the thermoplastic filament is coated on the high-performance fiber yarn through a pultrusion coating die. The pultrusion coating die is provided with an electric heating head, a resin injection tube, a yarn channel and a resin flow channel. The electric heating head heats the entire pultrusion coating die to ensure that the pultrusion coating die is at a suitable temperature and constant temperature; the yarn channel runs through the pultrusion coating die; one end of the resin injection tube is connected to an air compressor to inject the resin melt, and the end of the resin injection tube is located in the pultrusion coating die, and a resin flow channel is concentrically arranged on the outer periphery of the corresponding yarn channel, so that the high-performance fiber yarn fed with the resin melt through the yarn channel, when passing under the resin injection tube, the resin melt is evenly distributed along the resin flow channel and the outer contour of the high-performance fiber yarn, so as to achieve uniform coating of the resin corresponding to the thermoplastic filament. More preferably, the yarn channel can be customized to be circular, elliptical or racetrack-shaped. The pultrusion coating mold is a cube or a rectangular parallelepiped structure. When a rectangular parallelepiped structure is adopted, its length direction is along the direction of the yarn channel, which can provide a transition zone of temperature increase and temperature decrease in the mold to achieve uniform coating process.
[0012] In the above scheme, the braided composite yarn of step 1 can also be obtained by the following scheme, namely: A method for forming a thermoplastic braided composite propeller blade, the steps are as follows: Step 1: using thermoplastic fiber yarn and high-performance fiber yarn as raw materials, mixing thermoplastic filaments with the high-performance fiber yarn to obtain a braided composite yarn; Step 2, winding the braided composite yarn on a spindle using a doubling machine to form a yarn shaft for the braiding machine; Step 3: The propeller blade core mold is fixed on the mechanical arm through a three-claw chuck and corresponds to the position of the yarn shaft of the braiding machine. The braiding machine and the mechanical arm are started to make the braided composite yarn braided and coated on the surface of the propeller blade core mold according to the set rules to obtain a braided composite preform; Step 4: placing the braided composite preform in a molding die, heating and molding it to obtain a thermoplastic braided composite propeller blade.
[0013] The above scheme uses thermoplastic fiber yarn and high-performance fiber yarn as raw materials, and the thermoplastic fiber yarn and the high-performance fiber yarn are mixed and spun to form a thermoplastic fiber and high-performance fiber mixed yarn, also known as a thermoplastic braided mixed yarn. The yarn is characterized in that the two types of fibers can slide dislocation, the yarn is relatively flexible, and can be suitable for braiding of complex shapes.
[0014] at this time: The thermoplastic fiber yarn is any one of polyamide (PA, nylon), polyetheretherketone (PEEK), polyethylene (PE) and polyurethane (PU).
[0015] The high-performance fiber yarn is any one of carbon fiber, quartz fiber, silicon carbide fiber and basalt fiber.
[0016] The doubling ratio of thermoplastic fiber yarn to high-performance fiber yarn is 7~4:3~6. Under the premise of ensuring that there is no fiber filament breakage and fuzzing, the doubling speed is usually 20~50 m / min.
[0017] In the mixed and doubling process, the thermoplastic fiber yarn and the high-performance fiber yarn are respectively delivered to the yarn stop cylinder by two sets of delivery tension rollers, and mixed and doubling are performed at the yarn stop cylinder. More preferably, the delivery tension rollers are arranged in a high and low staggered manner, and the yarn stop cylinder is matched with the doubling tension roller to complete the mixed and doubling.
[0018] Compared with the prior art, the beneficial effects of the present invention are: the present invention can realize the efficient and automatic forming of complex and special-shaped thermoplastic woven composite propeller blades. The key to the present invention is to propose two forming technologies of thermoplastic woven yarns. On the basis of thermoplastic woven yarns, efficient and low-defect forming of complex and special-shaped woven composite preforms can be achieved, and then the efficient and automatic forming of complex and special-shaped woven composite propeller blades can be achieved through the molding process, which is conducive to greatly reducing the production cost while ensuring the quality of the preform. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0020] Figure 1 This is a schematic diagram of the molding process of the first braided composite yarn in this application; Figure 2 It is a schematic diagram of the three-dimensional structure of the pultrusion coating mold in this application; Figure 3 It is a schematic diagram of the side structure of the pultrusion coating mold in this application; Figure 4 It is a schematic diagram of the top view of the pultrusion coating mold in this application; Figure 5 for Figure 4 Sectional view in the middle MM direction; Figure 6 This is another three-dimensional structural schematic diagram of the pultrusion coating mold in this application; Figure 7 This is a schematic diagram of the molding process of the second braided composite yarn in this application; Figure 8 This is a schematic diagram of the structure of the propeller blade core mold in this application; Fig. 9 This is a schematic diagram of the assembly relationship between the propeller blade core mold, the braiding machine and the robotic arm in this application; Fig.10 This is a schematic diagram of the structure of the braided composite preform of the present application; Fig.11 This is a schematic diagram of the assembly relationship between the braided composite preform and the molding die in this application.
[0021] Numbers in the figure: A. high-performance fiber yarn; B. thermoplastic fiber yarn; 1. braided composite yarn; 11. resin; 2. pultrusion coating mold; 2a. main body; 21. electric heating head; 22. resin injection tube; 23. yarn channel; 24. resin flow channel; 3. mixed wire drawing mechanism; 31. first conveying tension roller; 32. second conveying tension roller; 33. yarn blocking cylinder; 34. wire drawing tension roller; 4. mechanical arm; 41. three-jaw chuck; 5. propeller blade core mold; 51. flange; 52. standard cylinder; 5a. braided composite preform; 6. braiding machine; 61. yarn shaft; 7. molded upper mold; 8. molded lower mold. DETAILED DESCRIPTION
[0022] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application clearer, the technical solutions in the embodiments of this application will be further described in detail below in conjunction with the drawings in the embodiments of this application. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit the technical solutions of this application. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.
[0023] It should be noted that when a component is referred to as being "fixed to" or "disposed on" another component, it may be directly or indirectly located on the other component. When a component is referred to as being "connected to" another component, it may be directly or indirectly connected to the other component. The directions or positions indicated by the terms "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the directions or positions shown in the accompanying drawings and are only for the convenience of description and should not be construed as limitations on the present technical solution.
[0024] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. "Multiple" means two or more, unless otherwise clearly and specifically defined.
[0025] Example 1
[0026] The present application provides a woven composite yarn 1 with high-performance fiber yarn A and thermoplastic filaments as raw materials. The thermoplastic filaments are heated to form a resin melt, which is then pressurized, extruded, and coated on the high-performance fiber yarn to form a composite structure. The following describes an embodiment of the present application in conjunction with the accompanying drawings.
[0027] See also Figures 2 to 5Schematic diagram of the structure of the pultrusion coating die 2: the pultrusion coating die 2 is provided with an electric heating head 21, a resin injection tube 22, a yarn channel 23 and a resin flow channel 24. The electric heating head 21 is arranged on the side wall of the pultrusion coating die 2. After the electric heating head 21 is connected to the power supply, the electric energy can be converted into thermal energy to heat the position corresponding to the resin flow channel 24 in the pultrusion coating die 2 to maintain it at a suitable temperature and constant temperature; the resin injection tube 22 is arranged on the top of the pultrusion coating die 2. After the thermoplastic filaments are heated to form a resin melt, the liquid resin melt is compressed by air The resin is fed into the resin injection pipe 22 by the machine, and the delivery pressure is maintained at about 0.2MPa; the resin flow channel 23 is located in the pultrusion coating mold 2, and the end of the resin injection pipe 22 is connected to the resin flow channel 23; the yarn channel 24 is set at the center position of the pultrusion coating mold 2, and the position relationship between the yarn channel 24 and the resin flow channel 23 satisfies the concentric relationship, so that after the resin melt is merged into the resin flow channel 23 through the resin injection pipe 22, it merges with the high-performance fiber yarn A on the yarn channel 24 at the corresponding position of the resin flow channel 23, and is evenly coated on the high-performance fiber yarn A.
[0028] See also Figure 1 , Figure 1 A schematic diagram showing the molding process of the woven composite yarn 1 of the composite structure of this embodiment is shown: the high-performance fiber yarn A specifically uses 12K carbon fiber, and the thermoplastic filament B specifically uses nylon filament, the two are mixed in a mass ratio of 1:1, and the nylon filament forms a liquid resin melt at a heating temperature of about 240°C.
[0029] Start the electric heating head 21, control the heating temperature to 240°C, start pressurizing when the temperature stabilizes, and inject liquid resin melt from the resin injection tube 22 at a delivery pressure of about 0.2MPa; the high-performance fiber yarn A is fed into the yarn channel 23 of the self-pultrusion coating mold 2, and the liquid thermoplastic resin is merged into the passing high-performance fiber yarn A through the resin flow channel 23, and the thermoplastic resin is completely filled and coated between the high-performance fiber yarns A and on the surface of the high-performance fiber yarn A; then naturally cool at room temperature to finally obtain a braided composite yarn 1, in which the high-performance fibers A cannot be displaced from each other, and the flexibility of the braided composite yarn 1 is lower than that of the simple high-performance fiber yarn A, and the friction resistance of the yarn is significantly improved, the damage during the yarn weaving process is reduced, and the fatal defects of the internal fiber breakage and kinking of the final composite material that affect the mechanical properties are reduced.
[0030] In the above scheme, the main body 2a of the pultrusion coating mold 2 can be made of Figures 1 to 5 The cube structure can also be Figure 6 As shown in the rectangular structure, the pultrusion coating mold 2 is elongated along the direction of the yarn channel 24, so that there is a transition zone of heating and cooling in the pultrusion coating mold 2, which gives the natural cooling process a more uniform characteristic and the structure of the formed braided composite yarn 1 is also more uniform.
[0031] The braided composite yarn 1 obtained by the above scheme is wound on the spindle through the doubling machine to form the yarn shaft 61 for the braiding machine 6. Figure 8 The propeller blade core mold 5 of the structure is connected to the mechanical arm 4 of the six-axis robot as follows: through the cooperation of the flange 51 and the three-jaw chuck 41 (the end of the propeller blade core mold 5 can be fixedly connected to the metal connector, one end of the metal connector is provided with a needle, when fixedly connected, the needle is inserted into the root part of the propeller blade core mold 5, and the other end of the metal connector is provided with a flange 51), and then according to the molding requirements, the operation program of the six-axis robot is pre-written and started, such as Fig. 9 As shown, the mechanical arm 4, the propeller blade core mold 5 and the braiding machine 6 are linked to reciprocately weave the braided composite yarn 1 on the surface of the propeller blade core mold 5 to form an outer braided mesh, and the braided outer braided mesh and the propeller blade core mold 5 are formed. Fig.10 A braided composite preform 5a is shown.
[0032] After the weaving is completed, the braided composite preform 5a is removed from the mechanical arm 4 of the six-axis robot and combined with Fig.11 , with the flange 51 and the standard cylinder 52 as positioning points, the braided composite preform 5a is positioned on the molding die, the upper molding die 7 and the lower molding die 8 are closed and vacuumized, and low-viscosity epoxy resin is poured into the molding die through the glue hole by an air compressor. After heating and curing, the upper molding die 7 and the lower molding die 8 are opened by a top screw. After opening the mold, the molded product is partially cut to obtain the final complex and special-shaped thermoplastic braided composite propeller blade.
[0033] Example 2
[0034] The present application provides a woven composite yarn 1 having a mixed structure formed by mixing and doubling high-performance fiber yarn A and thermoplastic fiber yarn B as raw materials. The embodiments of the present application are described below in conjunction with the accompanying drawings.
[0035] The high-performance fiber yarn A specifically uses 12K carbon fiber, and the thermoplastic fiber yarn B specifically uses nylon filament, and the added material ratio of the two is 5:5.
[0036] See also Figure 7 Schematic diagram of the structure of the mixed winding mechanism 3: It mainly includes a first conveying tension roller 31, a second conveying tension roller 32, a yarn blocking cylinder 33 and a doubling tension roller 34. The first conveying tension roller 31 and the second conveying tension roller 32 both contain multiple tension rollers, and the heights of adjacent tension rollers are different, so as to realize the high and low dislocation conveying of high-performance fiber yarn A and thermoplastic fiber yarn C. With the cooperation of the yarn blocking cylinder 33 and the doubling tension roller 34, the high-performance fiber yarn A and the thermoplastic fiber yarn C are entangled with each other during the high-speed drawing process, so as to realize the mixed doubling of the two yarns. The above two types of fiber yarns can slide dislocationwise, and the resulting braided composite yarn 1 has relatively good flexibility and can be suitable for weaving of complex shapes.
[0037] The braided composite yarn 1 obtained by the above scheme is wound on the spindle through the doubling machine to form the yarn shaft 61 for the braiding machine 6, and the propeller blade core mold 5 is connected to the mechanical arm 4 of the six-axis robot through the cooperation of the flange 51 and the three-jaw chuck 41 (the end of the propeller blade core mold 5 can be fixedly connected to the metal connector, and a needle is arranged at one end of the metal connector. When fixedly connected, the needle is inserted into the blade root part of the propeller blade core mold 5, and the flange 51 is arranged at the other end of the metal connector). According to the molding requirements, the operation program of the six-axis robot is pre-written and started, such as Fig. 9 As shown, the mechanical arm 4, the propeller blade core mold 5 and the braiding machine 6 are linked to reciprocately weave the braided composite yarn 1 on the surface of the propeller blade core mold 5 to form an outer braided mesh, and the braided outer braided mesh and the propeller blade core mold 5 are formed. Fig.10 A braided composite preform 5a is shown.
[0038] After the weaving is completed, the braided composite preform 5a is removed from the mechanical arm 4 of the six-axis robot and combined with Fig.11 , with the flange 51 and the standard cylinder 52 as positioning points, the braided composite preform 5a is positioned on the molding die, the upper molding die 7 and the lower molding die 8 are closed and vacuumized, and low-viscosity epoxy resin is poured into the molding die through the glue hole by an air compressor. After heating and curing, the upper molding die 7 and the lower molding die 8 are opened by a top screw. After opening the mold, the molded product is partially cut to obtain a thermoplastic braided composite propeller blade.
[0039] The above-mentioned embodiments only express several feasible implementation methods of the present invention, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention, and the embodiments are not used to limit the scope of protection in the claims of the present invention. For ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present invention, and all equivalent implementations or changes that do not depart from the present invention should be included in the technology of the present invention.
Claims
1. A method for forming a thermoplastic braided composite propeller blade, characterized in that: Here are the steps: Step 1: using thermoplastic filaments and high-performance fiber yarns as raw materials, heating the thermoplastic filaments to form a resin melt, and pressurizing and extruding the resin melt to coat the high-performance fiber yarn to obtain a braided composite yarn; Step 2, winding the braided composite yarn on a spindle using a doubling machine to form a yarn shaft for the braiding machine; Step 3: The propeller blade core mold is fixed on the mechanical arm through a three-claw chuck and corresponds to the position of the yarn shaft of the braiding machine. The braiding machine and the mechanical arm are started to make the braided composite yarn braided and coated on the surface of the propeller blade core mold according to the set rules to obtain a braided composite preform; Step 4: placing the braided composite preform in a molding die, heating and molding it to obtain a thermoplastic braided composite propeller blade.
2. The method for forming a thermoplastic braided composite propeller blade according to claim 1, characterized in that: The thermoplastic filament is any one of polyamide, polyetheretherketone, polyethylene and polyurethane, and the high-performance fiber yarn is any one of carbon fiber, quartz fiber, silicon carbide fiber and basalt fiber.
3. The method for forming a thermoplastic braided composite propeller blade according to claim 1, characterized in that: In step 1, the pressurization refers to setting the pressure at 0.1~0.3MPa.
4. The method for forming a thermoplastic braided composite propeller blade according to claim 1, characterized in that: In step one, the resin melt is coated on the high-performance fiber yarn through a pultrusion coating mold. The pultrusion coating mold is provided with an electric heating head, a resin injection tube, a yarn channel and a resin flow channel. The electric heating head heats the entire pultrusion coating mold to ensure that the pultrusion coating mold is at an appropriate temperature and a constant temperature; the yarn channel runs through the pultrusion coating mold; one end of the resin injection tube is connected to an air compressor to inject the resin melt, the end of the resin injection tube is located in the pultrusion coating mold, and a resin flow channel is concentrically arranged on the outer periphery of the corresponding yarn channel.
5. The method for forming a thermoplastic braided composite propeller blade according to claim 4, characterized in that: The pultrusion coating mold is a cube or a rectangular parallelepiped structure. When a rectangular parallelepiped structure is adopted, its length direction is along the direction of the yarn channel.
6. A method for forming a thermoplastic braided composite propeller blade, characterized in that: Here are the steps: Step 1: using thermoplastic fiber yarn and high-performance fiber yarn as raw materials, mixing thermoplastic filaments with the high-performance fiber yarn to obtain a braided composite yarn; Step 2, winding the braided composite yarn on a spindle using a doubling machine to form a yarn shaft for the braiding machine; Step 3: The propeller blade core mold is fixed on the mechanical arm through a three-claw chuck and corresponds to the position of the yarn shaft of the braiding machine. The braiding machine and the mechanical arm are started to make the braided composite yarn braided and coated on the surface of the propeller blade core mold according to the set rules to obtain a braided composite preform; Step 4: placing the braided composite preform in a molding die, heating and molding it to obtain a thermoplastic braided composite propeller blade.
7. A method for forming a thermoplastic braided composite propeller blade according to claim 6, characterized in that: The thermoplastic fiber yarn is any one of polyamide, polyetheretherketone, polyethylene, and polyurethane, and the high-performance fiber yarn is any one of carbon fiber, quartz fiber, silicon carbide fiber, and basalt fiber.
8. The method for forming a thermoplastic braided composite propeller blade according to claim 6, characterized in that: In step 1, the mixing and doubling ratio of the thermoplastic fiber yarn and the high-performance fiber yarn is 7~4:3~6.
9. The method for forming a thermoplastic braided composite propeller blade according to claim 6, characterized in that: In step one, in the mixing and doubling process, the thermoplastic fiber yarn and the high-performance fiber yarn are respectively sent to the yarn blocking cylinder through two sets of conveying tension rollers, and are mixed and doubling at the yarn blocking cylinder.
10. A method for forming a thermoplastic braided composite propeller blade according to claim 9, characterized in that: The conveying tension rollers are arranged in a high-low staggered manner, and the yarn blocking cylinder is matched with the yarn doubling tension rollers to complete the mixed yarn doubling.